Vestfrost refrigerator shows E3 and may run continuously or not cool correctly; defrost seems irregular.

Safety: Disconnect mains power before accessing the evaporator or wiring. Sharp metal edges can cause injury; wear cut-resistant gloves.

Steps to address E3 (defrost sensor):

• Access the evaporator area: Empty the freezer, remove drawers and the rear inner panel. If heavily iced, allow ice to melt (use towels, do not use sharp tools or heat guns directly on plastic).
• Locate the defrost sensor and thermal fuse: On many Vestfrost models, the defrost NTC and thermal fuse are clipped to the evaporator tubing or attached with aluminum tape.
• Check wiring and connectors: Look for burnt, brittle, or broken wires. Ensure connectors are fully seated and free of corrosion.
• Test the defrost NTC: With the unit unplugged, disconnect the sensor and measure resistance. At around 0°C (ice water), NTC sensors typically read higher resistance than at room temperature. If reading is infinite or near zero, replace the sensor.
• Test the thermal fuse (if present): Use a multimeter in continuity mode across the fuse. If open (no continuity), the fuse has blown and must be replaced with the exact temperature and current rating specified for Vestfrost.
• Replace faulty components: Install a new defrost sensor and/or thermal fuse assembly. Secure them in the same position on the evaporator to ensure accurate temperature sensing.
• Reassemble and test: Refit the evaporator cover, restore power, and monitor operation. The E3 code should clear after a successful defrost cycle.

Important: If the thermal fuse blew, also check the defrost heater and control board for faults that may have caused overheating.